回溯加递归

class Solution(object):
def solvePermutation(self, array):
self.helper(array, [])
def helper(self, array, solution):
# 递归的基线条件
if len(array) == 0:
print(solution)
return
for i in range(len(array)):
newSolution = solution + [array[i]]
self.helper(array[: i] + array[i + 1:], newSolution)
Solution().solvePermutation([“红”, “黄”, “蓝”, “绿”])